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Journal of Materials Science & Technology 2009年第2期25卷 264-268页

作者： Xianfeng Yang zhipeng xie Yong Huang State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

During thermal debinding in ceramic injection molding, the inhomogeneity of green body is a key origin of cracks. In this study, the impact of low molecular weight binders on the homogeneity of the green body was investigated. Incidence of cracks during thermal debinding indicated that the volume ratio of wax to stearic acid should be out of high viscosity and incompletely wetting region. In these two formulation regions, typical inhomogeneous microstructures were observed. By mercury intrusion method, it was shown that pore size distribution of the debinded compacts was determined by thermal degradation of low molecular weight binders. A particle-rich region model was established to predict the nucleation of cracks caused by solid loading fluctuation. The criterion of cracks nucleation was that local capillary force from solid loading fluctuation was larger than the suction force from the surroundings.

关键词： Ceramic injection molding Cracks Debinding Homogeneity

An aqueous ZnCl2/Fe(bpy)3Cl2 flow battery with mild electrolyte

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Frontiers of Materials Science 2020年第4期14卷 442-449页

作者： zhipeng xie Lulu WEI Shengwen ZHONG Faculty of Materials Metallurgy and Chemitry Jiangxi University of Science and TechnologyGanzhou 341000China

The kinetics of electrode reaction was investigated by cyclic voltammetry,and cyclic voltammograms show that the reversibility of the Fe(bpy)3^2+/Fe(bpy)^3+electrode reaction is better than that of the Zn/Zn^2+electrode reaction on the graphite ***,the Fe(bpy)3^2+ion diffusion in electrolyte is subject to greater resistance than that of the Zn^2+ion *** stability of the Fe(bpy)3Cl2 solution was investigated by UV-vis spectroscopy,and the performance of a mild redox flow battery employing ZnCl2 and Fe(bpy)3Cl2 in the NaCl aqueous solution with various membranes as the separator was also *** was found that the Celgard 3501 membrane cannot effectively prevent Fe(bpy)3^2+ions from leaking into anolyte,leading to the rapid failure of the flow *** the Nafion 115 membrane can be polluted by Fe(bpy)32+ions,it is not *** Nafion 115 membrane shows good selectivity,which can avoid Fe(bpy)32 ions from leakage into *** ZnCl2/Fe(bpy)3Cl2 flow battery with the Nafion 115 membrane exhibits the capacity retention of 80%after 200 cycles.

关键词： redox flow battery zinc bipyridine iron

In situ characterization of forearc serpentinized peridotite from the Sulu ultrahigh-pressure terrane: Behavior of fluid-mobile elements in continental subduction zone

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Geoscience Frontiers 2021年第4期12卷 110-121页

作者： zhipeng xie Keiko Hattori Youpu Dong Jian Wang Department of Earth Sciences Kunming University of Science and TechnologyKunming 650093PR China Department of Earth and Environmental Sciences University of OttawaOttawa K1N 6N5Canada College of Earth Sciences Jilin UniversityChangchunJilin 130061PR China

Serpentinized peridotites in the Yangkou(YK),Suoluoshu(SLS) and Hujialin(HJL) areas in the Sulu ultrahighpressure terrane represent the relic of ancient subcontinental lithospheric mantle below the North China *** protoliths,harzburgite and dunite,were variably hydrated by aqueous fluids released from subducting Yangtze *** rocks are enriched in fluid-mobile elements(FME) including Sb(42–333 times the depleted mantle value) and Pb(30–476 times).The degrees of the FME enrichment are comparable to that of the Himalayan forearc serpentinites,and greater than forearc mantle serpentinites from Marianas,suggesting that the degrees of FME enrichment in the forearc serpentinites are greater in continental subduction zones than those in the oceanic subduction *** after olivine in the SLS serpentinite shows higher degrees of enrichment in Sb and As than those for antigorite after both olivine and orthopyroxene in the YK *** antigorite has highly enriched in Pb,U,Cs,and LREE,but not for the *** abundance of FME in two different species of serpentine reflects the different temperature of *** temperature lower than 300 ℃,formed lizardite at shallow depths of the mantle wedge incorporates elements that are fluid mobile at low temperatures,such as Sb and *** the temperature greater than 300 ℃,formed antigorite at a relatively deep mantle wedge incorporate more FME from the subducting continental slab(or fragments),including Pb,U,Cs,LREE as well as Sb and *** eventual breakdown of antigorite(600–700 ℃) in prograde metamorphism would discharge water as well as FME into the subducting channel and/or the overlying mantle.

关键词： Continental subduction channel Subcontinental lithospheric mantle Fluid-mobile element Serpentinite Antigorite Lizardite

Effects of different backbone binders on the characteristics of zirconia parts using wax-based binder system via ceramic injection molding

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Journal of Advanced Ceramics 2016年第4期5卷 321-328页

作者： Jiaxin WEN zhipeng xie Wenbin CAO Xianfeng YANG School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100084 China State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and EngineeringTsinghua University Beijing 100084 China College of Physics and Electronics Science Changsha University of Science & Technology Changsha 410014 China

In this work,various backbone binders were used in wax-based binder system to formulate zirconia parts by ceramic injection molding (CIM).The effect of different backbone binders on the molding,debinding,and sintering behaviors was *** blending process,the feedstock using multi-polymer components exhibited more homogeneous structure compared with that using the mono-polymer ones due to the synergistic effect of *** solvent debinding,some defects such as 'slumping' and 'peeling' appeared in the parts containing ethylene-vinyl acetate copolymer (EVA),but they were not found in the parts with other thermal ***,as for the parts after sintering,the one using low density polyethylene (LDPE) and high density polyethylene (HDPE) as backbone binders presented a more uniform microstructure with finer zirconia grains among all the investigated compositions,and thus obtained the highest flexural strength (～949 MPa) and relative density (～98.9％).

关键词： ceramic injection molding (CIM) ZrO2 backbone binders solvent debinding sintering

Origin and advances in implementing blowing-snow effects in the Community Land Model

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Research in Cold and Arid Regions 2019年第5期11卷 335-339页

作者： ZeYong Hu zhipeng xie Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco‐Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100085China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100085China

Snow cover on the Tibetan Plateau(TP)is closely related to regional and continental biological and hydrological *** vast snow cover,special climatic conditions,and sparse vegetative cover over the TP facilitate the occurrence of blowing snow,leading to substantial heterogeneities in the snow cover and great promotion in the moisture supply from the land surface to the overlying atmospheric boundary ***,blowing-snow processes are significantly misrepresented or even neglected in current models,which causes considerable uncertainties of numerical model simulations and leads to erroneous estimates of snow-related processes in mountainous *** present in this paper a brief review of our work in the past 5 years to serve as a basis for further development and improvement of the land-surface *** studies can be divided into three parts:detection of the problems,development of the land-surface model,and application of the coupled model over the TP(the logical framework is presented in Figure 1).The origin and advances in the development of a land-surface model with consideration of blowing-snow effects are described herein;and the importance of blowing-snow processes in the land-surface model,especially over the TP,is *** expect that the blowingsnow studies over the TP will play a key role in documenting and understanding the land-surface processes(LSPs)and the cryospheric changes over the TP.

关键词： blowing snow land surface process community land model Tibetan Plateau

Diurnal and Seasonal Variations of CO2Fluxes and Their Climate Controlling Factors for a Subtropical Forest in Ningxiang

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Advances in Atmospheric Sciences 2015年第4期32卷 553-564页

作者： JIA Binghao xie Zhenghui ZENG Yujin WANG Linying WANG Yuanyuan xie Jinbo xie zhipeng State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

In this study, the diurnal and seasonal variations of CO2 fluxes in a subtropical mixed evergreen forest in Ningxiang of Hunan Province, part of the East Asian monsoon region, were quantified for the first time. The fluxes were based on eddy covariance measurements from a newly initiated flux tower. The relationship between the CO2 fluxes and climate factors was also analyzed. The results showed that the target ecosystem appeared to be a clear carbon sink in 2013, with integrated net ecosystem CO2exchange（NEE）, ecosystem respiration（RE）, and gross ecosystem productivity（GEP） of-428.8, 1534.8 and1963.6 g C m^-2yr^-1, respectively. The net carbon uptake（i.e. the-NEE）, RE and GEP showed obvious seasonal variability,and were lower in winter and under drought conditions and higher in the growing season. The minimum NEE occurred on12 June（-7.4 g C m^-2d^-1）, due mainly to strong radiation, adequate moisture, and moderate temperature; while a very low net CO2 uptake occurred in August（9 g C m^-2month^-1）, attributable to extreme summer drought. In addition, the NEE and GEP showed obvious diurnal variability that changed with the seasons. In winter, solar radiation and temperature were the main controlling factors for GEP, while the soil water content and vapor pressure deficit were the controlling factors in summer. Furthermore, the daytime NEE was mainly limited by the water-stress effect under dry and warm atmospheric conditions, rather than by the direct temperature-stress effect.

关键词： net ecosystem exchange diurnal and seasonal variations climate controlling factors subtropical mixed forest East Asian monsoon r

Alkaline zinc-based flow battery: chemical stability, morphological evolution, and performance of zinc electrode with ionic liquid

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Frontiers of Materials Science 2024年第1期18卷 113-121页

作者： Tianyong Mao Jing Dai Meiqing Xin Deliang Zeng zhipeng xie Jiangxi Province Key Laboratory of Power Batteries and Materials Jiangxi University of Science and TechnologyGanzhou 341000China

Zinc-based flow battery is an energy storage technology with good application prospects because of its advantages of abundant raw materials,low cost,and environmental *** chemical stability of zinc electrodes exposed to electrolyte is a very important issue for zinc-based *** paper reports on details of chemical stability of the zinc metal exposed to a series of solutions,as well as the relationship between the morphological evolution of zinc electrodes and their properties in an alkaline *** corrosion of zinc electrodes by the electrolyte will change their surface ***,we observed that chemical corrosion is not the main contributor to the evolution of zinc electrode surface morphology,but the main contributor is the Zn/Zn^(2+)electrode *** morphological evolution of zinc electrodes was controlled by using ionic liquids,1-ethyl-3-methylimidazolium acetate(EMIA),and 1-propylsulfonic-3-methylimidazolium tosylate(PSMIT),and the electrode performance was recorded during the morphological evolution *** was observed that the reversible change of zinc electrode morphology was accompanied by better electrode performance.

关键词： alkaline medium morphological evolution zinc-based flow battery new energy

Kinetics mechanism of microwave sintering in ceramic materials

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Science China(Technological Sciences) 2009年第9期52卷 2727-2731页

作者： HAO HongShun XU LiHua HUANG Yong ZHANG XiaoMeng xie zhipeng Department of Inorganic Non-metallic Materials University of Science and Technology BeijingBeijing 100083China Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Based on the traditional sintering model incorporating the characteristic of microwave sintering, the ionic conductance diffusion mechanism in microwave sintering was studied. A flat-ball model was presented to describe the kinetics process in microwave sintering, and was applied to the sintering process of TZP and ZrO2-Al2O3 ceramics. The results indicate that the shrinkage rate of materials in microwave sintering is proportional to t2/3 and r-4/3, respectively, where t is the sintering time and r is the particle radius. Whereas, the shrinkage rate of materials in conventional sintering is proportional to sintering time t2/5. Our model suggests that microwave sintering is faster than conventional sintering, which shows a good agreement with the experimental observation in sintering process of TZP and ZrO2-Al2O3.

关键词： microwave sintering ionic conductance kinetics sintering mechanism

Electrochemical performance of La_(2)NiO_(4+δ)-Ce_(0.55)La_(0.45)O_(2−δ)as a promising bifunctional oxygen electrode for reversible solid oxide cells

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Journal of Advanced Ceramics 2021年第2期10卷 328-337页

作者： Pengzhang Li Wei Yang Chuanjin Tian Wenyan Zhao Zhe Lü zhipeng xie Chang-An Wang School of Materials Science and Engineering Jingdezhen Ceramic InstituteJingdezhen333403China School of Physics Harbin Institute of TechnologyHarbin150001China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China

In this work,La_(2)NiO_(4+δ)-Ce_(0.55)La_(0.45)O_(2−δ)(denoted as LNO-xLDC)with various LDC contents(x=0,10,20,30,and 40 wt%)were prepared and evaluated as bifunctional oxygen electrodes for reversible solid oxide cells(RSOCs).Compared with the pure LNO,the optimum composition of LNO-30LDC exhibited the lowest polarization resistance(Rp)of 0.53 and 0.12Ω·cm^(2)in air at 650 and 750℃,*** enhanced electrochemical performance of LNO-30LDC oxygen electrode was mainly attributed to the extended triple phase boundary and more oxygen ionic transfer *** hydrogen electrode supported single cell with LNO-30LDC oxygen electrode displayed peak power densities of 276,401,and 521 mW·cm^(−2)at 700,750,and 800℃,***,the electrolysis current density of the single cell demonstrated 526.39 mA·cm^(−2) under 1.5 V at 800℃,and the corresponding hydrogen production rate was 220.03 mL·cm^(−2)·h^(−1).The encouraging results indicated that LNO-30LDC was a promising bifunctional oxygen electrode material for RSOCs.

关键词： La_(2)NiO_(4+δ)(LNO) oxygen electrode electrochemical performance reversible solid oxide cells(RSOCs)

Structural whiteness of the multi-component glaze dependence on amorphous photonic crystals

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Frontiers of Materials Science 2019年第2期13卷 206-215页

作者： Hongquan ZHAN Chuanqi WU Ce DENG Xiaohong LI zhipeng xie Changan WANG School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China State Key Lab of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China

A kind of enhancing mechanism of structural whiteness dependence on amorphous photonic crystal (APC) structure is introduced in this paper. In the glaze system composed of albite, kaolin, talc, calcite, quartz, titanium dioxide and zinc oxide, the APC structure will be produced by using quartz as a variable to induce the phase separation. Under different polarities between Ti, Zn etc. and Siion, the separated spheres with the core-shell structure can be obtained and then make up opal-like APCs in the glaze layer. In addition to inner and outer layers of core-shell spheres, the calculated results of refractive indices clearly show the great difference between the particles and the matrix. As a result of different refractive indices, the multiple scatting of visible light plays a key rote in the structural whiteness. However, due to the decrease of the cationic content, APCs with the reverse opal structure would be formed in the interface between glaze and body. Ultimately, the glaze appearance reveals extremely high structural whiteness due to the special APC structure.

关键词： structural whiteness amorphous photonic crystal core-shell structure